Polysaccharides Carbohydrates that glycogen

Carbohydrates are an important food source for most organisms. Glucose, fructose, and sucrose are small carbohydrate molecules that can be broken down rapidly to provide quick energy for cells. Large amounts of energy are stored in carbohydrate macromolecules called polysaccharides. For example, glycogen is a polysaccharide used... 

Carbohydrates are classified based upon the products formed when they are hydrolyzed. Monosaccharides are simple sugars that cannot be broken down into simpler sugars upon hydrolysis. Examples of monosaccharides are glucose, ribose, deoxyribose, and fructose. Disaccharides contain two monosaccharide units and yield two monosaccharides upon hydrolysis. Examples of disaccharides are lactose, maltose, and sucrose. Polysaccharides are polymers of monosaccharide units and yield many individual monosaccharides upon hydrolysis. Examples of polysaccharides are starch, glycogen, and cellulose. 

Starch is the polysaccharide that plants use for storing energy. Many animals make use of a similar energy-storage carbohydrate called glycogen. It is often stored in muscle tissue as an energy source. 

Starch is a plant polysaccharide that we encounter in our food, but we in fact manufacture a very similar substance ourselves in our liver and in our muscles we have our own carbohydrate energy store, glycogen. This is closely similar to plant amylopectin, with a branched, tree-like molecule, the only difference being that glycogen is more highly branched. 

There are three chemical compounds that form the building blocks of food carbohydrates, hits (or hpids), and proteins. Carbohydrate molecules, which are found in fruits, vegetables, starches, and dairy products, consist of atoms of carbon, hydrogen, and oxygen, chemically bonded in a ratio of 1 2 1. Monosaccharides and disaccharides such as glucose, fructose, and sucrose have just one or two molecules of this kind and are known as simple sugars. Polysaccharides like starch, glycogen, and cellulose (an important component of dietary fiber) have several carbohydrate molecules and are known as complex... 

There are three types of carbohydrate starch, non-starch polysaccharide and sugars. Of the simple sugars, disaccharides such as sucrose, maltose and lactose are far more abundant in the diet than monosaccharides such as glucose and fructose. All forms of carbohydrate that can be digested and absorbed can be converted to glycogen for storage in liver or skeletal muscle. 

Biological Functions of Oligosaccharides and Polysaccharides. Polysaccharides serve two important biological roles. Glycogen and starch are polymers of glucose units linked in a(l —> 4) linkages that serve as carbohydrate reserves for animals, bacteria, and plants. Because these polymers are readily converted to intermediates for pathways that yield metabolic energy, they can also be... 

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